In the wake of the collapse of Malta's spectacular arch, which UK coastal features are under threat from the unrelenting forces of wind and water?

Hypothetical reconstruction of the largest extinct megapode, Progura gallinacea (right), with a modern Brush-turkey and a Grey Kangaroo.
Artwork by E. Shute, from photos by Tony Rudd, Kim Benson and Aaron CamensJune 14, 2017